Chalky

iTrader: (2)

I see a lot of tunes where the AFR is pretty much flat-lined on NA cars @ 12.9 to 13.1. Anyone document adding fuel to bump up peak torque?
I know GM adds fuel in PE to coincide with max torque numbers.

Zick

iTrader: (18)

I tend to run my AFR around 12.5 to peak TQ, then up to 13 to peak HP and back down to 12.5-12.8.

Chalky

iTrader: (2)

Pretty much what I have done. I know GM sets up the PE table the same way but with a lot more fuel throughout.

I dyno'd in April and we pretty much flatlined AFR throughout the range @ 12.9. We ran out of time to try tweaking AFR in 4400-5200. Just wondering what gains are available by richening up AFR for max tq.

GuitsBoy

iTrader: (4)

I run:

1.13965 1.13965 1.13965 1.13965 1.13965 1.13965 1.13965 1.13965 1.13965 1.13965 1.14355 1.14355 1.13965 1.13574 1.13184 1.13184 1.13184 1.13379 1.13574

dynocar

I've tried it on many NA cars, works on some, not on others. We are most prone to detonation at peak tq because of peak cyl pressures. If a given car is at the verge of detonation there, a little extra fuel seems to help power. But setting timing at the verge of detonation is usually not the most powerful tune. So my tuning answer, liike always, it depends.

GuitsBoy

iTrader: (4)

Do you guys also dip down the timing by 2 or 3 degrees at peak torque?

Chalky

iTrader: (2)

When you many, are you referring to LSx motors or all makes? Draw any conclusions on LSx motors?

dynocar

Yes, many LSX engines.

gametech

iTrader: (1)

Dynocar's statements apply to a lot more than just lsx engines.

Tripintaz

I have my LS6 tuned to be a little richer (12.6:1)at peak torque as well as drop 2-3 degrees of timing right before and right at peak torque. Then after peak torque i ramp the timing back up 3 degrees and lean it out to 13.1:1 all the way to redline.
I always thought this was the way it was supposed to be done...Im curious what others opinions are

These air fuel ratios were measured with my LM1 wideband on the street.

Checkmate

iTrader: (2)

Yes but I run 13.0 across the board. My old camaro made less power at 12.5 then 13 at peak torque.

dynocar

Correct, from an A/F ratio perspective, the LSXs vary from engine to engine, combo to combo just like other mass produced four stroke engines.